[coreboot-gerrit] [L] Change in coreboot[main]: mb/asus/p8z77-v: Add support to reconfigure PCIe lanes

[Keith Hui (Code Review)]

Attention is currently required from: Angel Pons, Nicholas Chin.

Hello Bill XIE, Nicholas Chin, build bot (Jenkins),

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/85413?usp=email

to look at the new patch set (#19).

Change subject: mb/asus/p8z77-v: Add support to reconfigure PCIe lanes
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mb/asus/p8z77-v: Add support to reconfigure PCIe lanes

Bill Xie documented in his initial code drop that he was unsuccessful
in reproducing all the PCIe configurations possible with vendor
firmware. I obtained a boardview to this board and have identified the
PCIe lane topology and the control signals required to reproduce all
the vendor PCIe configurations.

This patch:

1. Changes GPIO20 of PCH to GPIO input so coreboot can detect a
card inserted into PCIEX1_2.
2. Adds an nvram option to allow selecting PCIEX16_3 bandwidth between
auto (x1, but tries to sense for a card in PCIEX1_2 and allocate lanes
accordingly), x1 (forces PCIEX1_2), x2 (disables PCIEX1_1,
not a vendor option), x4.
3. Adds an nvram option to force PCIe lane 4 to serve ASM1061 and its
two SATA 6Gbps ports.
4. Programs SIO GPIOs and soft strap as appropriate.
5. Removes all GPIO5 settings from devicetree to eliminate interference.
6. Implements PCH soft strap reflashing support as a separate unit of
asus/p8x7x-series, available via a new Kconfig, as p8z77-v_le_plus and
Sabertooth Z77 also have similar needs.

BUG=https://ticket.coreboot.org/issues/583

Change-Id: If41197a1f817a48c209d25fc1ae461ec97ccf16c
Signed-off-by: Keith Hui 
Co-authored-by: Bill XIE 
---
M src/mainboard/asus/p8x7x-series/Kconfig
M src/mainboard/asus/p8x7x-series/Makefile.mk
A src/mainboard/asus/p8x7x-series/ifd.c
M src/mainboard/asus/p8x7x-series/mainboard.c
A src/mainboard/asus/p8x7x-series/pcielane.h
M src/mainboard/asus/p8x7x-series/variants/p8z77-v/cmos.default
M src/mainboard/asus/p8x7x-series/variants/p8z77-v/cmos.layout
M src/mainboard/asus/p8x7x-series/variants/p8z77-v/early_init.c
M src/mainboard/asus/p8x7x-series/variants/p8z77-v/gpio.c
M src/mainboard/asus/p8x7x-series/variants/p8z77-v/overridetree.cb
A src/mainboard/asus/p8x7x-series/variants/p8z77-v/pcielane.c
11 files changed, 401 insertions(+), 9 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/13/85413/19